Leonardo DiCaprio in 'Shutter Island', Martin Scorsese, Robert DeNiro in 'Raging Bull'

Gentlemen, draw decades and come out fighting! Shutter Island marks the fourth collaboration of Leonardo DiCaprio with Martin Scorsese over the past eight years, which inspires inevitable comparisons with the first four films that Scorsese made with Robert DeNiro from 1973 to 1980. But DiCaprio himself is smart enough to realize that there's no real comparison, telling Moviefone: "That to me is the greatest cinema duo of all time, so I wouldn't dare even have that conversation."

Of course, I am not Leo, and so I dare to start the conversation. DeNiro and Scorsese were contemporaries, growing up not far from each other in Greenwich Village in the 1940s and 50s. The films on which they worked together defined them as actor and filmmaker, as well as influencing an entire generation. DiCaprio's post-Titanic star power has helped Scorsese get dream projects made and enabled the director to dabble magnificently in studio genre films. Scorsese's deft touch has drawn superb, wide-ranging performances from a man young enough to be his son.

Gangs of New York (2002) vs. Mean Streets (1973)
In both films, the putative star was outshone by an actor in a supporting role. As Bill the Butcher, Daniel Day-Lewis dwarfed a sometimes uncertain DiCaprio (age 28) in the rocky epic, while, essaying the wild Johnny Boy, DeNiro (age 30) stole the show from Harvey Keitel. It's not that DiCaprio and Keitel weren't good, it's that Bill and Johnny were the most dynamic characters. Mean Streets sings; Gangs whistles when it works.